Method of time-synchronized data transmission in induction type power supply system

ABSTRACT

The present invention provides a method of time-synchronized data transmission in induction type power supply system, comprising timers and programs installed in a supplying-end module and a receiving-end module to predict the time for generating the trigger signal at the receiving-end end and perform steps for detecting signals to avoid omission. Under the condition of high power transmission, power output on the supplying-end coil is pre-reduced prior to the time expected for receiving trigger data, making the main carrier wave amplitude decrease in a short time period. In every process of data transmission, timers are mutually calibrated and synchronized again to transmit power without detecting and receiving in the period when no data are expected to be transmitted, thus preventing interference of power load noise and enabling the induction type power supply system to transmit data code stably.

This application is a Continuation-In-Part of application Ser. No.13/154,965, filed on Jun. 7, 2011, now pending. The patent applicationidentified above is incorporated here by reference in its entirety toprovide continuity of disclosure.

This application claims the priority benefit of Taiwan patentapplication number 101108610 file on Mar. 14, 2012.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of time-synchronized datatransmission in induction type power supply system, particularly to themethod of data transmission in power supply system that enablessynchronous transmission of power and data signals to prevent mutualinterference with noise resistance ability. By using timers installed inmicroprocessors of a supplying-end module and a receiving-end module andoperations of programs, the supplying-end module arranges the time tostart detecting trigger signals in advance, adjust power output to makeit easy to recognize signals and calibrate and synchronize the timersautomatically, and shut off detection to prevent interference withelectric load noise when no data is transmitted, thus achieving thefunction of transmitting data signals stably.

2. Description of the Related Art

In the digital age, digital products are seen everywhere in our life,for example, portable electronic devices such as digital cameras, mobilephones, music players (MP3 and MP4) and etc. These portable electronicdevices and products tend to become light, thin, short and small indesign. The first requirement for portability is power supply, and themost common solution is to install rechargeable batteries in portableelectronic devices, so that these devices can be recharged whenelectricity runs out. Yet, now everyone has a number of portableelectronic devices with a specific charger compatible with each of them.To use a charger for charging a portable electronic device, it isnecessary to link the connection interface (plug) of the charger with areceptacle and plug the connector of the charger at the other end intothe portable electronic device. While repeated plugging and pulling ofconnection interfaces easily causes damage to its terminals in the longperiod, induction type power supply systems can avoid this problem bytransmitting power through coil induction without terminal contact.

Usually, functional settings or compilation and transmission of data,etc. shall be conducted for electronic devices in addition to charging.For some electronic devices, settings and input can be conducteddirectly, but for other electronic devices (e.g. music players (MP3,MP4, etc), digital cameras, electronic watches, portable game machinesand consoles), settings cannot be conducted directly and otherelectronic devices (such as computers, personal digital assistants,etc.) are required to fulfill functional settings and data transmission.Besides, usually charging and data transmission cannot be conductedsynchronously and must be carried out separately. Induction type powersupply systems (or so-called wireless chargers) currently available inthe marketplace rely on two coils to operate: one acting as asupplying-end coil to transmit power and the other acting as areceiving-end coil to receive power. Since wireless power energy cancause dangers and heat up metal objects on the same principle as aninduction stove, it is also easy to cause damage or failure of objectsthat are being charged due to heating effect.

For existing induction type power supply systems, the most importanttechnical problem is the ability to identify objects placed on thesupplying-end coil. Like a cooking induction stove, induction power cantransmit enormous energy of electromagnetic waves, which may heat upmetal objects and cause dangers if directed towards these objects. Tosolve this problem, some firms try to develop technologies ofidentifying objects, and after putting efforts for several years, findthat the best solution that depends on a receiving-end coil of areceiving-end module to transmit feedback signals and on a supplying-endcoil to receive signals. The most important core technology is toachieve the function of transmitting data through the induction coils.It is difficult to transmit data stably through induction coils forsupplying power, because main carrier waves are transmitted byhigh-power electricity and may be affected by interferences occurringduring use of power systems. Moreover, since it also constitutes afrequency-changer control system, the operating frequency of carrierswill not be fixed; furthermore, when the induction coil is used tosupply power, a wireless communication channel (such as infrared,Bluetooth, radio frequency identification (RFID) or WiFi communicationchannel, etc) is established separately. However, adding wirelesscommunication devices into the existing induction type power supplysystem will lead to increase of manufacturing cost for the system.

When induction type power coils are used to transmit data, one problemthat should be noticed is how to transmit and receive datasynchronously. Like the method of transmitting data over RFID, themethod of transmitting data over supplying-end coil is operated in theway that the supplying-end coil transmits the main carrier to thereceiving-end coil and the receiving-end circuit feeds back bycontrolling load changes. In existing design of induction type powersupply systems, power energy and data are transmitted in unidirectionalway, i.e. the power energy (LC main oscillating carrier transmitted fromthe supplying-end coil) is transmitted from the supplying-end module tothe receiving-end module, while the data code is fed from thereceiving-end module to the supplying-end module. But the receiving-endmodule only receives energy that is either strong or weak from thesupplying-end module without emitting data signals of communicationactively, and can feed back only after getting close to thesupplying-end module and receiving power. And the supplying-end modulecannot transmit data codes if not supplying power energy, so there arestill considerable limitations and inconveniences in use of theinduction type power supply system.

Refer to FIGS. 30 and 31, which illustrate the structures of receivingpower and data feedback of the receiving-end module. As shown in thesefigures, there are two types of structural design for this purpose:resistance type and capacitance type. The resistance type modulation offeedback signals originates from the passive RFID technology, whichrelies on resistance of the receiving-end coil to switch feedbacksignals to the supplying-end coil for reading, as applied in a wirelesscharging system disclosed in US Patent Publication No. 20110273138,entitled Wireless Charging System (Taiwan Patent Publication No.201018042, entitled Wireless Charging System) filed by Access BusinessGroup (Fulton). According to this invention, the load resistor of theswitch placed on the rear side of the receiving rectifier, or Rcm inFIG. 31, is used to make changes in impedance characteristics on thereceiving-end coil that is fed back to the supplying-end coil. Thesechanges will be analyzed by the detection circuit on the supplying-endcoil, and then decoded by the software installed in the processor of thesupplying-end module.

Referring to FIGS. 32 and 33, FIG. 32 illustrates the signal status onthe supplying-end coil. When the Rcm switch is closed, it will cause theimpedance on the receiving-end coil to drop down, making the amplitudeon the supplying-end coil increase after feeding back to thesupplying-end coil. Then the asynchronous serial format in UARTcommunication mode is used for encoding, i.e. to interpreting logic datacodes by determining whether the modulation status changes at this timepoint in a fixed time cycle. However, this way of encoding may result ina problem that modulation load is kept switching on within a cycle time.

Refer to FIGS. 34 and 35, which illustrate the data transmission formatin qi specifications. These figures show a data transmission frequencymodulated and demodulated with the 2 KHz timing frequency. It can beworked out that the longest duration of modulation load conduction is acycle in a signal feedback. In UART communication mode, the duration ofmodulation load conduction does not affect system functions. Ininduction type power supply system, however, the state of modulationload conduction will affect the state of power supply, because the maincarrier at the supplying-end is used to supply power and can transmitstrong current drive force due to the coupling effect of thesupplying-end module and receiving-end module. But the resistor load atthe receiving-end module needs to withstand feedback drive currents;when power increases, the power to be withstood at Rcm will increase,too. Besides, in the process of modulation, the electric currents thatoriginally go to the receiving-end module for output will be shunted byRcm, thus reducing the output capability at the receiving-end module.Moreover, signals are easy to recognize only when the cycle time forsignal modulation is far less than that of transmission frequency. Asmain carrier waves in induction type power supply system can onlyoperate at a lower frequency (roughly 100˜200 KHz) as a result ofcomponents' performance restraints or in accordance with laws andregulations electromagnetic interference, while data transmissiondepends on modulation of main carrier waves, the data transmissionfrequency must be far lower than the main carrier wave frequency toensure smooth operation. Due to the conflict of the above conditions,when the power of induction type power supply system is increased, datamodulation with resistor loads will not work any more.

Since signal modulation loads need to absorb considerably large electriccurrents and it leads to the problem of power loss following powerincreases, making it impossible to use this method, some firms propose anew method of capacitive signal modulation. In US Patent Publication No.20110065398, entitled Universal Demodulation And Modulation For DataCommunication In Wireless Power Transfer by Hongkong-based ConvenientPower HK Ltd (referring to FIGS. 36 and 37), capacitors and switches areadded at the receiving-end module to feed signals to the supplying-endmodule and generate changes in the voltage, current and input on thesupplying-end coil, and data signals are identified through analysis ofthese three variables of signals. The shortcoming of this method lies inthat all three variables are so weak that several amplification circuitsare needed for analysis, making the circuit cost increase significantly.

As shown in FIGS. 38, 39, 40, 41 and 42, coil amplitudes or coil outputpower will increase during signal modulation to enable the analysiscircuit to identify the amount of variance and transmit it to themicroprocessor for analysis. In the figure of analysis amplification,when the amplitude of the induction type power supply system reachesPoint A, it will increase to Point B following signal modulation, andmay increase to Point C or D if the modulation energy increases (lowresistance is used at Rcm in the previous example). In the inductiontype power supply system, the amplitude changes with the load state atthe receiving-end module. Under the condition of high power output, theamplitude may operate at Point C or D, and may move to Point E ifsignals are modulated under such circumstance. This can be seen as anoverload reaction, and at this time, the power supply system will losethe capability to increase amplitudes through signal modulation totransmit data, which may lead to the system failure. In light of thislimitation, the induction type power supply system is designed to makeits amplitude reach a lower position of Point A or B with low poweroutput. When the output power is increased, the amplitude needs to beincreased to Point C or D, resulting in system failure.

Therefore, to solve this problem, all firms that engage in this fieldfocus on how to increase the power for the induction type power supplysystem

SUMMARY OF THE INVENTION

In view of the aforesaid problems and disadvantages, the inventor hascollected related information, conducted assessments and takenconsiderations in many aspects, and based on many years of his ownexperience in this field, finally invented the method oftime-synchronized data transmission in induction type power supplysystem that allows electronic products to transmit power and datasignals synchronously, making a supplying-end module transmit electricpower to a receiving-end module and receive the data signals fed backfrom the receiving-end module within a planned cycle by synchronizingthe timer without any influence of electric load noise.

The primary object of the present invention is to install timers andprograms in microprocessors of a supplying-end module and areceiving-end module. The supplying-end module can predict the time forgenerating the trigger signal at the receiving-end module, during whichthe supplying-end module performs steps for detecting signals to avoidomission in a short time period. Under the condition of high powertransmission, the induction type power supply system performspre-reduction of power output on a supplying-end coil prior to the timeexpected for generating trigger data, making the main carrier waveamplitude decrease in a short time period and making it easy for thetrigger signals from the receiving-end module to be analyzed by thesupplying-end module under the condition of high power transmission.Each time when data are transmitted, timers are mutually calibrated andsynchronized again, so that the supplying-end module only transmitspower and does not detect and receive data in the period when no dataare expected to be transmitted, thus preventing interference of powerload noise and enabling the induction type power supply system totransmit data code stably in power supply applications.

The secondary object of the present invention is to electrically connecta microprocessor of a supplying-end module with a power drive unit, asignal analysis circuit, a coil voltage detection circuit, a displayunit, a power supply unit and a grounding terminal. The power drive unitis further connected with a resonant circuit and a supplying-end coil toestablish inductive relationship between the supplying-end coil andreceiving-end coil for power and signal transmission. Besides, amicroprocessor of a receiving-end module is electrically connected witha voltage detection circuit, a breaker protection circuit, a voltagestabilizing circuit, an amplitude modulation circuit, a direct currentstep-down transformer, a rectifier and filter circuit and a resonantcircuit respectively. The timers and programs installed in thesupplying-end and receiving-end microprocessors are used to predict thetime for generating trigger data, and the supplying-end module caneliminate signal noise of electric power other than data signals. Unlikethe non-time-synchronization method adopted in the past that is unableto distinguish between data and signal noise and needs long feedbacksignals to distinguish data from noise, resulting in consumption of morepower, the present invention can shorten the time for feeding backsignals from the receiving-end module to its maximum and generatingshort-pulse signals similar to changes in output load of thereceiving-end module, thus achieving the purpose of saving energy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an operation flow chart for supplying power in accordance withthe present invention (1).

FIG. 2 is an operation flow chart for supplying power in accordance withthe present invention (2).

FIG. 3 is an operation flow chart for supplying power in accordance withthe present invention (3).

FIG. 4 is an operation flow chart of the receiving-end module afterreceiving power in accordance with the present invention (1).

FIG. 5 is an operation flow chart of the receiving-end module afterreceiving power in accordance with the present invention (2).

FIG. 6 is an operation flow chart for synchronous power supply and datatransmission in accordance with the present invention (1).

FIG. 7 is an operation flow chart for synchronous power supply and datatransmission in accordance with the present invention (2).

FIG. 8 is an operation flow chart for synchronous power supply and datatransmission in accordance with the present invention (3).

FIG. 9 is an operation flow chart for synchronous power supply and datatransmission in accordance with the present invention (4).

FIG. 10 is an operation flow chart for synchronous power supply and datatransmission in accordance with the present invention (5).

FIG. 11 is an operation flow chart for synchronous power supply and datatransmission in accordance with the present invention (6).

FIG. 12 is an operation flow chart of initialization of the transmissionpower pre-reduction check and control program before the transmissionfrequency is ready to reduce in accordance with the present invention.

FIG. 13 is an operation flow chart of initialization of the transmissionpower recovery check and control program before the transmissionfrequency is ready to restore in accordance with the present invention.

FIG. 14 is a schematic circuit diagram of the supplying-end module inaccordance with the present invention.

FIG. 15 is a schematic circuit diagram of the receiving-end module inaccordance with the present invention.

FIG. 16 is a chart illustrating waveform amplitude variation at datasignal modulation point in accordance with the present invention.

FIG. 17 illustrates a control signal of the N-type MOSFET componentdrawing of the receiving-end module in accordance with the presentinvention.

FIG. 18 is a schematic drawing illustrating data signal transmission inaccordance with the present invention.

FIG. 19 illustrates a signal during detection of the supplying-endmodule in accordance with the present invention.

FIG. 20 illustrates a signal indicating extended power transmissionafter the supplying-end module detects the trigger signal from thereceiving-end module in accordance with the present invention.

FIG. 21 illustrates a signal in a data frame (main loop gap) duringpower transmission in accordance with the present invention.

FIG. 22 illustrates a signal of data frame contents in accordance withthe present invention.

FIG. 23 illustrates a signal of the start bit length in a data frame inaccordance with the present invention.

FIG. 24 illustrates a signal of logic 0 bit length in the data frame inaccordance with the present invention.

FIG. 25 illustrates a signal of logic 1 bit length in the data frame inaccordance with the present invention.

FIG. 26 illustrates a signal of transmission bit content in the dataframe in accordance with the present invention.

FIG. 27 is a presentation of power pre-reduction of the supplying-endcoil signals in accordance with the present invention (1).

FIG. 28 is a presentation of power pre-reduction of the supplying-endcoil signals in accordance with the present invention (2).

FIG. 29 illustrates a signal processed with anti-noise method inaccordance with the present invention.

FIG. 30 is a schematic circuit diagram of the structure of receivingpower and feedback by the receiving-end module according to conventionalQi specifications (1).

FIG. 31 is a schematic circuit diagram of the structure of receivingpower and feedback by the receiving-end module according to conventionalQi specifications (2).

FIG. 32 illustrates a signal in a conventional induction type powersupply system disclosed in US Patent Publication No. 20110273138 (1).

FIG. 33 illustrates the signal in a conventional induction type powersupply system disclosed in US Patent Publication No. 20110273138 (2).

FIG. 34 illustrates the data transmission format according to theconventional Qi specifications (1).

FIG. 35 illustrates the data transmission format according to theconventional Qi specifications (2).

FIG. 36 is a schematic circuit diagram of data modulation anddemodulation in the wireless power transfer disclosed in US PatentPublication No. 20110065398 (1).

FIG. 37 is a schematic circuit diagram of data modulation anddemodulation in the wireless power transfer disclosed in US PatentPublication No. 20110065398 (2).

FIG. 38 is a circuit diagram of resistor type signal modulation inconventional Ti specifications.

FIG. 39 is a waveform of resistor type signal modulation in conventionalTi specifications.

FIG. 40 is a circuit diagram of capacitor type signal modulation inconventional Ti specifications.

FIG. 41 is a waveform drawing of capacitor type signal modulation inconventional Ti specifications.

FIG. 42 is a chart illustrating waveform amplitude variation at datasignal modulation point.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

To achieve the aforesaid objects and functions as well as the techniquesadopted in the present invention and its fabrication, examples of thepreferred embodiment of the present invention are given below toillustrate its features and functions in detail by referring to theaccompanying drawings.

Referring to FIGS. 1, 2, 14, 15, 19, 20, 21, 22, 23, 24, 25 and 26, aninduction type power supply system disclosed in the present inventionincludes a supplying-end module 1 and a receiving-end module 2. A methodof transmitting power and data signals from said modules to a presetelectronic device comprises the steps of:

(100) starting program initialization by a supplying-end microprocessorand setting the timing length of the trigger pulse, start bit, logicstate, end bit and data transmission loop and other functions followingsupply of power from a power source 161 of a power supply unit 16 in thesupplying-end module 1.

(101) setting the detection signal output frequency by a supplying-endmicroprocessor 11 with the frequency converter program and then stoppingoutput frequency to a power driver unit 12;

(102) starting a standby timer by the supplying-end microprocessor 11and entering into the sleeping and power-saving state after shuttingdown the output, and waking up upon completion of timing;

(103) starting and transmitting the detection signal by thesupplying-end microprocessor 11 upon completion of standby timing toactivate the receiving-end module 2 close to a supplying-end coil 171and then starting a voltage comparator installed in the supplying-endmicroprocessor 11;

(104) starting to count the detection time and detecting if there is atrigger signal on the signal analysis circuit 13 through the voltagecomparator in the supplying-end microprocessor 11; proceeding to step(105) if there is no trigger signal; otherwise, proceeding to step(107);

(105) deciding that there is no receiving-end module 2 close to thesupplying-end module 1 if no trigger signal is found by thesupplying-end microprocessor 11 in the detection period and preparing toenter into standby mode;

(106) detecting the signal from a coil voltage detection circuit 14 bythe supplying-end microprocessor 11 and checking if the voltage fallswithin the set range; proceeding to step (101) to reset the detectionsignal output frequency if the voltage does not fall within the setrange; otherwise, proceeding to step (102) and shutting off the output;

(107) transmitting a trigger signal from the timer installed in thesupplying-end microprocessor 11 to examine the signal check flag anddetermine if the first trigger signal is delivered, proceeding to step(108) if no, otherwise proceeding to step (110);

(108) deciding that the receiving-end module 2 gets close to thesupplying-end coil 171 according to the first trigger signal andextending the detection signal transmission time by the supplying-endmicroprocessor 11 to continuously transmit power to the receiving-endmodule 2 through the supplying-end coil 171 and make it operate;

(109) marking the signal check flag as an issued trigger signal by thesupplying-end microprocessor 11, starting the trigger signal timer toget ready for detecting the next trigger and proceeding to step (104);

(110) sending a trigger signal from the timer of the supplying-endmicroprocessor 11 and checking if the start bit length is confirmed;proceeding to step (111) if the start bit length is not confirmed;otherwise, proceeding to step (112);

(111) checking by the supplying-end microprocessor 11 if the issue timeof the current trigger signal and time length of the first triggersignal conform with the range of the start bit length; proceeding tostep (112) if yes, and proceeding to step (113) if not;

(112) marking the start bit flag as confirmation completed by the timerof the supplying-end microprocessor 11, resetting and restarting thetrigger signal timer to get ready for detecting the next trigger andcontinuing to implement step (311);

(113) deciding that no desired receiving-end module 2 is getting closeby the supplying-end module 11 according to that the start bit signallength does not comply with the set value, getting ready for shuttingdown the output and proceeding to step (105).

As shown clearly in FIGS. 1, 2, 3, 4, 5, 14, 15, 22, 23, 24, 25, 26, 2728 and 29, after receiving the power from the supplying-end module 1,the receiving-end module 2 implements the steps of:

-   -   (200) after the receiving-end module 2 receives the startup        power from the supplying-end module 1, starting the        initialization program and setting the timing length of the        trigger pulse, start bit, logic state, end bit and data        transmission loop;    -   (201) converting the terminal analog voltage of the resistor 221        into a numerical value and transmitting it to the Tx data buffer        in the receiving-end microprocessor 21 of the receiving-end        module 2 by using the receiving-end microprocessor 21 for the        first time;    -   (202) measuring the data transmission loop timing length by time        and setting it as a timing startup point by the receiving-end        microprocessor 21 (50 mS, for example);    -   (203) transmitting a first trigger pulse from the receiving-end        microprocessor 21 and measuring the start bit length by time        (2.5 mS, for example);    -   (204) completing the timing of the start bit length,        transmitting the data in Tx data buffer and setting the number        of bits inside as Tx data bits by the receiving-end        microprocessor 21;    -   (205) rotating the bits in Tx data buffer and reading out the        least significant bit (LSB) for logic decision through internal        instructions in the receiving-end microprocessor 21 and adding        one count to the data counter;    -   (206) judging the logic state by the receiving-end        microprocessor 21; proceeding to step (207) if the logic state        is 0, or proceeding to step (208) if the logic state is 1;    -   (207) transmitting the trigger pulse from the receiving-end        microprocessor 21; if the logic state is decided to be 0,        starting timing of the logic 0 length and proceeding to step        (209) (2 mS, for example);    -   (208) transmitting the trigger pulse from the receiving-end        microprocessor 21; if the logic state is decided to be 1,        starting timing of the logic 1 length and proceeding to step        (209) (3 mS, for example);    -   (209) terminating timing by the receiving-end microprocessor 21        and checking if the number displayed on the data counter is        equal to that of data bits; proceeding to step (210) if yes, and        proceeding to step (205) if not;    -   (210) completing transmission of data bits from the        receiving-end microprocessor 21, transmitting a trigger pulse        and starting timing of the end bit length (2.5 mS, for example);    -   (211) finishing timing of the end bit length in the        receiving-end microprocessor and transmitting a trigger pulse as        the last trigger identification signal in the data transmission;    -   (212) converting the terminal analog voltage of the resistor 221        in the receiving-end microprocessor 21 into a numerical value        and transmitting it to the Tx data buffer in the receiving-end        microprocessor 21.    -   (213) waiting for timing of the data transmission loop to be        completed, so that the first trigger pulse can match the set        length (for example, 50 mS) and proceeding to step (202) before        the start bit is transmitted in every data transmission.

Moreover, the induction type power supply system disclosed in thepresent invention comprises a supplying-end module 1 and a receiving-endmodule 2.

The supplying-end module 1 includes a supplying-end microprocessor 11,in which operation and control programs, signal analysis softwareprograms with anti-noise function and other related software programs, atimer used for timing of signal pulse spacing length and a voltagecomparator used to detect pulse signal triggering are built. Thesupplying-end microprocessor 11 is electrically connected with a powerdrive unit 12, a signal analysis circuit 13, a coil voltage detectioncircuit 14, a display unit 15 and a power supply unit 16 respectively.The power drive unit 12 has a MOSFET driver 121 connected with thesupplying-end microprocessor 11, a high-side MOSFET component 122 and alow-side MOSFET component 123 respectively, where both MOSFET componentsare connected to a resonant circuit 17, and the high-side MOSFETcomponent 122 is further connected with the power supply unit 16electrically. The signal analysis circuit 13 comprises a rectifier diode133 electrically connected to the resonant circuit 17, a plurality ofresistors 131 electrically connected in series to the rectifier diode133, and a plurality of capacitors 132 connected in parallel to theseries of resistors 131. The power supply unit 16 comprises a powersource 161, a detection divider resistor 162 and a detection dividerresistor 163 connected in series and a direct current (DC) step-downtransformer 164, and is connected with the power drive unit 12. Theresonant circuit 17 is connected with a supplying-end coil 171 capableof transmitting power and receiving data signals.

The receiving-end module 2 includes a receiving-end microprocessor 21,in which operation, control and related software programs and a timerused for timing of transmitted signal pulse spacing length areinstalled. The receiving-end microprocessor 21 is connected with avoltage detection circuit 22, a rectifier and filter circuit 23, anamplitude modulation circuit 24, a breaker protection circuit 25, avoltage stabilizing circuit 26 and a direct current (DC) step-downtransformer 27 respectively. The voltage detection circuit 22 has aplurality of resistors 221 connected electrically in series to thereceiving-end microprocessor 21 and detection points 222 electricallyconnected with the resistors 221, the rectifier and filter circuit 23,the breaker protection circuit and the DC step-down transformer 27respectively. The rectifier and filter circuit 23 includes a rectifier231 and a capacitor 232 that are respectively connected in parallel withthe voltage detection circuit 22, the breaker protection circuit 25 andthe DC step-down transformer 27, and the rectifier 231 is connected inparallel with the resonant circuit 28 and a receiving-end coil 281through the rectifier 231. The receiving-end coil 281 is connected inseries with the amplitude modulation circuit 24. The amplitudemodulation circuit 24 comprises a resistor 241 and an N-type MOSFETcomponent 242 connected in series to the resistor 241. The breakerprotection circuit 25 includes a resistor 251, a P-type MOSFET component252 and an N-type MOSFET component 253, of which the N-type MOSFETcomponent 253 is utilized to electrically connect to the receiving-endmicroprocessor 21. Besides, the P-type MOSFET component 252 iselectrically connected with a buffer capacitor 261 and a DC step-downtransformer 262 linked electrically with a power output terminal 263 onthe voltage stabilizing circuit 26. Furthermore, the voltage detectioncircuit 22, breaker protection circuit 25, voltage stabilizing circuit26 and DC step-down transformer 27 are electrically connected to thereceiving-end microprocessor 21 respectively, and the voltage detectioncircuit 22, breaker protection circuit 25 and DC step-down transformer27 are electrically connected to the rectifier and filter circuit 23.The rectifier and filter circuit 23 is further connected via therectifier 231 to the resonant circuit 28 electrically. Thus, theresonant circuit 28 is electrically connected with the receiving-endcoil 281.

The induction type power supply system in the above embodiment iscapable of transmitting power and data synchronously by using thesupplying-end coil 171 of the supplying-end module 1 and thereceiving-end coil 281 of the receiving-end module 2, and can securestable transmission of data signals regardless of the power to betransmitted. For transmission of high power between the supplying-endmodule 1 and receiving-end module 2, the power is reduced first to allowthe data trigger signal to be transmitted successfully and thenrestored; during the period when no data signal is transmitted, thesupplying-end module 1 will shut down the voltage comparator used todetect the trigger signal, i.e., deactivate the function of receivingdata trigger signal, so that the noise interference resulting from loadchanges in the power transmission will not be processed and recognizedby the supplying-end microprocessor 11.

However, the above function needs to be achieved through precise andcareful arrangement between the supplying-end module 1 and receiving-endmodule 2, so that the supplying-end module 1 predicts the time totransmit data signals by the receiving-end module 2, starts the voltagecomparator used for detecting the trigger signal in the supplying-endmicroprocessor 11 only during transmission of data trigger signals andwill not perform other operations during data transmission, except fordetecting the trigger signals from the receiving-end module 2. After thepower for transmitting electric power is increased, the operatingvoltage wave amplitude is lowered from Point C (or point D, referring toFIG. 16) to Point B prior to data signal triggering, so that themodulated trigger signal wave amplitude will increase from Point B toPoint C or D. The trigger signal processed in this way is still capableof increasing amplitude changes, thus solving the problem that thesignal wave amplitude at Point E is lower than that at Point C or Dfollowing high power modulation, which may result in system error.Moreover, each time when data signals are transmitted, the supplying-endmodule 1 will also calibrate its timer against the synchronous time ofthe receiving-end module 2 to secure correct timing in every process ofdata transmission, and the data signals are received by thesupplying-end coil 171 correctly in the process when the receiving-endmodule 2 is transmitting trigger signals. For the receiving-endmicroprocessor 21 of the receiving-end module 2, it is only necessary totransmit trigger pulses without the need to consider the length of datasignals to be modulated, as it can shorten the time for data signalmodulation to the largest degree, reduce the energy loss in the processof modulation, and reduce vibrations of the receiving-end coil 281caused by current changes during transmission of data signals.

As shown clearly in FIGS. 1, 2, 3, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,19, 20, 21, 22, 23, 24, 25, 26, 27, 28 and 29, according the embodimentof the present invention, the method for synchronous transmission ofpower and data signals in the induction type power supply systemcomprises the steps of:

(300) initializing a data signal receiving program in the supplying-endmicroprocessor 11 and setting values of main timing loop and data lengthranges after power is supplied from the power source 161 of thesupplying-end module 1;

(301) the supplying-end microprocessor 11 starting and transmitting themain timing loop of data transmission, and performing programmedoperations at the scheduled time;

(302) the supplying-end microprocessor 11 transmitting the main timingloop, and performing initialization of a transmission powerpre-reduction check and control program within 3 mS before the maintiming loop of transmission is cleared to zero;

(303) checking the trigger signal that indicates the first trigger rangeof the start signal; if a trigger signal is found within 2.5 mS±0.5 mSprior to zero clearing of the timer for the main timing loop, proceedingto step (304); otherwise, proceeding to step (305);

(304) marking the signal check flag as a transmitted trigger signal,starting the trigger signal timer to prepare for the next trigger andproceeding to step (305);

(305) the supplying-end microprocessor 11 transmitting the main timingloop, and performing initialization of a transmission power recoverycheck and control program within 2 mS prior to zero clearing of thetimer for the main timing loop of transmission;

(306) the supplying-end microprocessor 11 transmitting the main timingloop, and performing initialization of the transmission powerpre-reduction check and control program within 0.5 mS prior to zeroclearing of the timer for the main timing loop;

(307) checking the trigger signal that indicates the second triggerrange of the start signal; if the bit length is found to be ininconformity with the set range within ±0.5 mS prior to zero clearing ofthe timer for the main timing loop of transmission, proceeding to step(308); if both triggers are completed and the length range is satisfied,proceeding to step (311);

(308) recording a failed transmission if the supplying-endmicroprocessor 11 does not correctly receive two triggers whose bitlength falls within the set range, shutting off the voltage comparatorused for detecting the trigger signal, executing the transmission powerrecovery check and control program, and resetting the timing when themain timing loop returns to zero;

(309) deciding by the supplying-end microprocessor 11 if the number offailed transmission is greater than the set upper limit value;proceeding to step (310) if the upper limit value is reached; otherwise,proceeding to step (301);

(310) if the supplying-end microprocessor 11 does not receive anytrigger signal within the expected time period, deciding that datatransmission is failed, getting ready to terminate output from thesupplying-end coil 171 and entering into the standby mode;

(311) if the supplying-end microprocessor 11 receives two triggers ofthe start bit and finds out that the bit lengths fall within the setrange, deciding that the start bit signal is fed from the receiving-endmodule 2 correctly, clearing the timer for the main timing loop againand restarting it to synchronize the timer in the supplying-endmicroprocessor 11 with the timer for the main timing loop of datatransmission in the receiving-end microprocessor 21;

(312) starting to receive data bits, and after the timer for receivingdata bits is cleared to zero, restarting the supplying-endmicroprocessor 11;

(313) checking the signal flag that indicates completion of receiving todecide if a check is needed; proceeding to step (3131) if check isneeded; otherwise, proceeding to step (314);

(3131) performing initialization of the transmission power pre-reductioncheck and control program when the timer for detection of data bitreceiving runs for 2.25 mS in the supplying-end microprocessor 11;

(3132) checking the trigger signal by the supplying-end microprocessor11 and deciding that the data length of the end bit signal received is2.5 mS±0.5 mS;

(3133) executing the transmission power recovery check and controlprogram when the timer for detection of data bit receiving runs for 2.75mS in the supplying-end microprocessor 11;

(3134) data receiving completed by the supplying-end microprocessor 11,transferring the data into the supplying-end microprocessor 11 forinternal use and preparing to receive data in the next data transmissionloop, and then proceeding to step (301);

(3135) deciding that data transmission is failed if no triggeringhappened within the expected time period, executing the transmissionpower recovery check and control program, and proceeding to step (308);

(314) performing initialization of the transmission power pre-reductioncheck and control program when the timer for detection of data bitreceiving runs for 1.75 mS in the supplying-end microprocessor 11;

(315) checking the trigger signal by the supplying-end microprocessor11; if the triggering happened within 2 mS±0.5 mS, deciding that thedata length of logic 0 signal received is 2 mS and proceeding to step(3151); if no triggering happened, proceeding to step (316);

(3151) clearing the timer for detection of data bit receiving to zero atthe triggering point and restarting it, then marking the received datasignal as logic 0;

(3152) executing the transmission power recovery check and controlprogram when the timer for detection of data bit receiving runs for 0.25mS in the supplying-end microprocessor 11;

(3153) storing the received logic bits into Rx data buffer cyclically insequence from the most significant bit to the least significant bit, andadding one count to the data counter;

(3154) checking if the number of data transmission has been equal tothat of transmitted data bits; if yes, proceeding to step (3155);otherwise, proceeding to step (3156);

(3155) the supplying-end microprocessor 11 having received incompletedata bit, and preparing to receive the next trigger, and proceeding tostep (312);

(3156) the supplying-end microprocessor 11 having received a completedata bit, marking the end bit flag that needs to be checked, preparingto receive the next trigger and proceeding to step (302);

(316) executing the transmission power recovery check and controlprogram (3051) when the timer for detection of data bit receiving runsfor 2.25 mS in the supplying-end microprocessor 11;

(317) executing the transmission power recovery check and controlprogram (3021) when the timer for detection of data bit receiving runsfor 2.75 mS in the supplying-end microprocessor 11;

(318) checking the trigger signal by the supplying-end microprocessor11, deciding that the data length of the logic 1 bit signal received is3 mS if the triggering happened within 3 mS±0.5 mS, and proceeding tostep (319); proceeding to step (3135) if the triggering does not happen;

(319) clearing the timer for detection of data bit receiving to zero andrestarting the supplying-end microprocessor, and then marking thereceived data as logic 1;

(320) executing the transmission power recovery check and controlprogram when the timer for detection of data bit receiving runs for 0.25mS in the supplying-end microprocessor 11 and then proceeding to step(3152);

Moreover, initialization of transmission power pre-reduction check andcontrol program in step (302) comprises the steps of:

(3021) initializing the transmission power pre-reduction check andcontrol program in the supplying-end microprocessor 11;

(3022) checking if the testing voltage on the supplying-end coil 171 ofthe supplying-end module 1 has reached the set value to pre-reduce theoutput power; if the set value has not been reached, proceeding to step(3023); otherwise, proceeding to step (3025);

(3023) if the set value range having not been reached for powerpre-reduction, starting the voltage comparator in the supplying-endmicroprocessor 11 and preparing to detect the trigger signal;

(3024) terminating the transmission power pre-reduction check andcontrol program and returning to the master system program;

(3025) recording the current operating frequency first, and thenincreasing the output frequency to the power drive unit 12 to reduce theoutput frequency from the supplying-end coil 171 when the set valuerange for power pre-reduction is reached;

(3026) starting the voltage comparator in the supplying-endmicroprocessor 11 to prepare for detecting the trigger signal, settingthe marking for reduced power and proceeding to step (3024).

Furthermore, initialization of the transmission power recovery check andcontrol program in step (305) comprises the steps of:

(3051) initializing the transmission power recovery check and controlprogram in the supplying-end microprocessor 11;

(3052) checking if there is any marking made for power pre-reduction; ifthere is no marking, proceeding to step (3053); otherwise, proceeding tostep (3055);

(3053) no marking made for power pre-reduction in the supplying-endmicroprocessor, shutting off the voltage comparator in the supplying-endmicroprocessor 11 directly to make it unable to be triggered within thetime period when no data is received and prevent from interfering withdata transmission;

(3054) terminating the transmission power recovery check and controlprogram and returning to the master system program;

(3055) restoring to the operating frequency recorded previously to makethe output frequency to the power drive unit 12 and amplitudes of theoutput frequency from the supplying-end coil 171 return to the signalstate prior to power pre-reduction;

(3056) shutting off the voltage comparator in the supplying-endmicroprocessor 11 to prevent noise and system error, eliminatingmarkings for power pre-reduction and proceeding to step (3054).

Referring to FIGS. 14, 15, 16, 17 and 18, when the receiving-end module2 receives high-power electric energy, the N-type MOSFET component 242of the amplitude modulation circuit 24 is turned on (high potential ofthe N-CH MOSFET G pin causes D-S conduction). Therefore, less time forhigh-potential conduction and trigger can result in less loss. In thepresent invention, the time for high-potential conduction and trigger(t) is 0.02 mS approximately (according to an example of the preferredembodiments of the present invention, and shall not be construed aslimiting the time for conduction and trigger (t), which varies withactual design requirements), and a trigger signal is generated at eachtime of high-potential conduction (t) calculated at the edge of thetrigger. In the receiving-end module 2, the calibrated interval betweenthe first trigger signal (start bit) and the first trigger signal in thenext data frame (start bit) is 50 mS (according to an example of thepreferred embodiments of the present invention, shall not be construedas limiting the calibrated interval time which may vary with actualdesign requirements). As subsequent data frames may have different bitlengths (time) as a result of different contents of bytes (logic 0,bit-0 or logic 1, bit-1), the first trigger signal (start bit) is takenas the starting point for calculating time.

In an example of preferred embodiments of the present invention, boththe start time and end time of data frames are 2.5 mS. Since data maycomprise logic 0 (2 mS) or logic 1 (3 mS), the receiving-endmicroprocessor 21 of the receiving-end module 2 will begin to receivedata signals only after confirming that the start bit length is 2.5 mS,and will receive an end bit signal of 2.5 mS again after having finishedreceiving the trigger signal (logic 0 and logic 1) for eight times.After the signals (8 triggers) between the start bit and end bit arereceived completely and flags of the start bit and end bit of 2.5 mS aretransmitted successfully, these signals and flags can constitute correctdata, thus reducing noise interference to analysis by the supplying-endmodule 1 in the process of data signal transmission and preventing datafrom being processed improperly (the above figures or descriptions areintended to illustrate an example of preferred embodiments of thepresent invention and shall not be construed as constraints over figuresor descriptions of the present invention, and they may differ accordingto actual design requirements)

The timer is also required in the supplying-end microprocessor 11 of thesupplying-end module 1 (the timing length may be set as 50 mS ordesigned in a different way) to predict the time needed for eachtransmission of data signals, and shall be synchronized with the timerin the receiving-end microprocessor 21 of the receiving-end module 2. Ifsynchronization is implemented at the same time of triggering of thestart bit, the timers of the supplying-end module 1 and receiving-endmodule 2 cannot be synchronized unless the start bit is interpretedcorrectly.

After the timers of the supplying-end module 1 and receiving-end module2 are synchronized, the supplying-end module 1 (refer to the No. 8-1curve in FIG. 18) may start the comparator for detecting signals justbefore data is transmitted from the receiving-end module 2 (refer to theNo. 8-2 curve in FIG. 18). Besides, the power output from thesupplying-end module 1, if considerably high (refer to the No. 8-3section in FIG. 18), may be reduced in advance to facilitate triggersignal transmission from the receiving-end module 2. However, the timeof power reduction is very short (roughly 0.25 mS to 0.5 mS), and thesection occurring on the receiving-end module 2 where transmission powerreduces will be buffered by the buffer capacitor 261 of the voltagestabilizing circuit 26, thus preventing data signal output from thereceiving-end module 2 from being affected.

It should be noted that the above descriptions are given to illustrateexamples of preferred embodiments of the present invention and shall notbe construed as limiting the appended patents claims of the presentinvention. In the present invention, the method of time-synchronizeddata transmission in induction type power supply system achievestransmission of power from the supplying-end microprocessor 11 of thesupplying-end module 1 to the receiving-end coil 281 of thereceiving-end module 2 and feedback of data signals from thereceiving-end coil 281 to the supplying-end coil 171 of thesupplying-end module 1 by using the timers embedded in the supplying-endmicroprocessor 11 and receiving-end microprocessor 21 to synchronizetiming and receiving trigger signals, thus enabling data signals to bestably transmitted synchronously while the supplying-end module 1transmits power. So it can achieve the purpose of reducing transmissionloss of data signals without affecting power transmission between thesupplying-end module 1 and the receiving-end module 2. In oneembodiment, the supplying-end microprocessor 11 of the supplying-endmodule 1 reduces the power to facilitate data transmission during highpower transmission and restores the original power following data signaltransmission, with the advantage of increasing the maximum transmissionpower of induction type power supply systems. Thus, the presentinvention can also achieve the utility function to synchronize chargingand stable transmission of data signals. It is hereby stated thatprocesses, embodiments, devices or configurations, etc. that can achievesaid effect shall be covered by the present invention, and that allmodifications and equivalent structural changes shall be included in theappended patent claims of the present invention.

In practical applications, the method of time-synchronized datatransmission in induction type power supply system has the advantages asfollows:

-   -   (1) both the supplying-end microprocessor 11 and the        receiving-end microprocessor 21 includes a timer used to        synchronize timing and predict the time for triggering data        signals, so as to achieve high-power transmission of electric        energy and stable transmission of data signals;    -   (2) the supplying-end microprocessor 11 can coordinate with the        trigger time of the receiving-end microprocessor 21 to reduce        high-power electric energy in advance during data transmission        and restore the original power following completion of data        transmission, without affecting transmission of electric power        and data due to power reduction and increase in short period of        time.

Therefore, the present invention relates to the method oftime-synchronized data transmission in induction type power supplysystem. It uses the timers installed in the supplying-end microprocessorof the supplying-end module and receiving-end microprocessor of thesupplying-end module for synchronization when data signals are fed fromthe receiving-end module to the supplying-end module, thus achievingstable and synchronous transmission of power and data signals betweenthe receiving-end module and supplying-end module and stabilizing systemoperation for power transmission. However, all the above descriptionsare given to illustrate an example of preferred embodiments of thepresent invention and shall not be construed as limiting the patentclaims of the present invention. It is hereby stated that allmodifications and equivalent principle changes made according to thesedescriptions and drawings shall be included in the appended patentclaims of the present invention.

In summary, the method of time-synchronized data transmission ininduction type power supply stem as disclosed in the present inventioncan achieve its functions and objects when applied practically.Therefore, the present invention is really an excellent one withpractical applicability and can satisfy the terms and conditions forpatentability of a utility model. While the application of patent isfiled pursuant to applicable laws, your early approval will be highlyappreciated so as to guarantee benefits and rights of the inventor whohas worked hard at this invention. For any question, please do nothesitate to inform the inventor by mail, and the inventor will try hisbest to cooperate with you.

1. A method of time-synchronized data transmission in induction typepower supply system to achieve transmission of data signals and powerbetween a supplying-end module used to transmit power and areceiving-end module used to feed back data signals, the methodcomprising the steps of: (a) starting program initialization by asupplying-end microprocessor and setting the timing length of thetrigger pulse, start bit, logic state, end bit and data transmissionloop and other functions following transmission of power from a powersource of the supplying-end module; (b) setting the detection signaloutput frequency by the supplying-end microprocessor with the frequencyconverter program to stop output frequency to a power driver unit; (c)starting a standby timer by the supplying-end microprocessor andentering into the sleeping and power-saving state after shutting downthe output, and waking up upon completion of timing; (d) starting andtransmitting the detection signal upon completion of standby timing toactivate the receiving-end module close to the supplying-end coil andthen starting a voltage comparator installed in the supplying-endmicroprocessor; (e) starting to count the detection time and detectingif there is a trigger signal on the signal analysis circuit with thevoltage comparator in the supplying-end microprocessor; proceeding tostep (h) if there is no trigger signal; otherwise, proceeding to step(f); (f) deciding that there is no receiving-end module close to thesupplying-end module if no trigger signal is found in the detectionperiod and preparing to enter into standby mode; (g) detecting thesignal from the coil voltage detection circuit in the supplying-endmicroprocessor and checking if the voltage falls within the set range;proceeding to step (b) to reset the detection signal output frequency ifthe voltage does not fall within the set range; otherwise, proceeding tostep (c) and shutting off the output; (h) transmitting a trigger signalfrom the timer to examine the signal check flag and determine if a firsttrigger signal is delivered, proceeding to step (i) if not, otherwiseproceeding to step (k); (i) deciding that the receiving-end module getsclose to the supplying-end coil according to the first trigger signaland extending the detection signal transmission time to continuouslytransmit power to the receiving-end module through the supplying-endcoil and make it operate; (j) marking the signal check flag as an issuedtrigger signal, starting the trigger signal timer to get ready fordetecting the next trigger and proceeding to step (e); (k) sending atrigger signal from the time of the supplying-end microprocessor andchecking if the start bit length is confirmed; proceeding to step (l) ifthe start bit length is not confirmed; otherwise, proceeding to step(m); (l) checking if the issue time of the current signal and timelength of the first trigger signal conform with the range of the startbit length; proceeding to step (m) if yes, and proceeding to step (n) ifnot; (m) marking the start bit flag as confirmation completed, resettingand restarting the trigger signal timer to get ready for detecting thenext trigger; (n) deciding that no desired receiving-end module isgetting close by the supplying-end module if the start bit signal lengthdoes not comply with the set value, getting ready for shutting down theoutput and proceeding to step (f).
 2. The method of time-synchronizeddata transmission in induction type power supply system according toclaim 1, wherein the supplying-end module comprises a supplying-endmicroprocessor, which is electrically connected with an power driveunit, a signal analysis circuit, a coil voltage detection circuit, adisplay unit, a power supply unit and a grounding terminal respectively;the power drive unit is electrically connected with a resonant circuit,and the resonant circuit, the signal analysis circuit and the coilvoltage detection circuit are respectively and electrically connectedwith a supplying-end coil able to transmit power signals.
 3. The methodof time-synchronized data transmission in induction type power supplysystem according to claim 1, wherein the receiving-end module comprisesa receiving-end microprocessor, which is electrically connected with avoltage detection circuit, a breaker protection circuit, a voltagestabilizing circuit, an amplitude modulation circuit and a directcurrent step-down transformer respectively; the breaker protectioncircuit, the direct current step-down transformer and the voltagedetection circuit are respectively and electrically connected with arectifier and filter circuit respectively, and the rectifier and filtercircuit and amplitude modulation circuit are further respectivelyconnected with a resonant circuit and a receiving-end coil.
 4. Themethod of time-synchronized data transmission in induction type powersupply system according to claim 1, wherein after receiving the powerfrom the supplying-end module in step (i), the receiving-end moduleproceeds the following steps: (i01) receiving the startup power from thesupplying-end module, starting the initialization program and settingthe timing length of the trigger pulse, start bit, logic state, end bitand data transmission loop; (i02) converting the terminal analog voltageof the resistor in the receiving-end microprocessor into numerical valueand transmitting the numerical value to the Tx data buffer in thereceiving-end microprocessor of the receiving-end module for the firsttime; (i03) measuring the data transmission loop timing length by timeand setting it as a timing start point; (i04) transmitting a firsttrigger pulse and starting timing of the start bit length; (i05)completing the timing of the start bit length, transmitting the data inTx data buffer and setting the number of bits inside as Tx data bits;(i06) rotating the bits in Tx data buffer and reading out the leastsignificant bit (LSB) for logic decision through internal instructionsin the receiving-end microprocessor and adding one count to the datacounter; (i07) judging the logic state; proceeding to step (i08) if thelogic state is 0, or proceeding to step (i09) if the logic state is 1;(i08) transmitting the trigger pulse; if the logic state is decided tobe 0, starting timing of the logic 0 length and proceeding to step(i10); (i09) transmitting the trigger pulse; if the logic state isdecided to be 1, starting timing of the logic 1 length and proceeding tostep (i10); (i10) terminating timing and checking if the numberdisplayed on the data counter is equal to that of data bits; proceedingto step (i11) if yes, and proceeding to step (i06) if not; (i11)completing transmission of data bits, transmitting a trigger pulse andstarting timing of the end bit length; (i12) finishing timing of the endbit length and transmitting a trigger pulse as the last triggeridentification signal in the data transmission; (i13) converting theterminal analog voltage of the resistor in the receiving-endmicroprocessor into numerical value and transmitting the numerical valueto the Tx data buffer in the receiving-end microprocessor; (i14) waitingfor timing of the data transmission loop to be completed, so that thefirst trigger pulse can match the set length and proceeding to step(i03) before the start bit is transmitted in every data transmission. 5.The method of time-synchronized data transmission in induction typepower supply system according to claim 1, wherein in the step of markingthe start bit flag as confirmation completed in step (m), the triggersignal timer is cleared to zero and restarted for detecting nexttrigger, and the timers installed in the supplying-end and receiving-endmodules are calibrated at the same time.
 6. A method oftime-synchronized data transmission in induction type power supplysystem to achieve transmission of data signals and power between asupplying-end module used to transmit power and a receiving-end moduleused to feed back data signals, the method comprising the steps of: (a1)initializing the data signal receiving program in the supplying-endmodule and setting the values of main timing loop and other itemsfollowing transmission of power from the supplying-end module; (b1)starting and transmitting the main timing loop of data transmission andperforming programmed operations at the scheduled time; (c1) performinginitialization of the transmission power pre-reduction check and controlprogram within 3 mS before the timer of the main timing loop oftransmission is cleared to zero; (d1) checking the trigger signal thatindicates the first trigger range of the start signal; if a triggersignal is found within 2.5 mS±0.5 mS prior to zero clearing of the timerfor the main timing loop of transmission, proceeding to step (e1);otherwise, proceeding to step (f1); (e1) marking the signal check flagas a transmitted trigger signal, starting the trigger signal timer toprepare for the next trigger and proceeding to step (f1); (f1)performing initialization of a transmission power recovery check andcontrol program within 2 mS prior to zero clearing of the timer for themain timing loop of transmission; (g1) performing initialization of thetransmission power pre-reduction check and control program within 0.5 mSprior to zero clearing of the timer for the main timing loop oftransmission; (h1) checking the trigger signal that indicates the secondtrigger range of the start signal; if the bit length is found to be ininconformity with the set range within ±0.5 mS prior to zero clearing ofthe timer for the main timing loop of transmission, proceeding to step(i1); if both triggers are completed and the length range is satisfied,proceeding to step (m1); (i1) recording a failed transmission if thesupplying-end microprocessor does not correctly receive two triggerswhose bit lengths comply with the set range, shutting off the voltagecomparator used for detecting the trigger signal, executing thetransmission power recovery check and control program, and resetting thetiming when the main timing loop returns to zero; (j1) deciding if thenumber of failed transmission is greater than the set upper limit value;proceeding to step (k1) if the upper limit value is reached; otherwise,proceeding to step (b1); (k1) if no trigger signal is received withinthe expected time period, deciding that data transmission is failed,getting ready to terminate output from the supplying-end coil andentering into the standby mode; (m1) if two triggers of the start bitfall within the set range, deciding that the start bit signal is fedfrom the receiving-end module correctly, clearing the timer for the maintiming loop again and restarting the timer to synchronize the timer inthe supplying-end microprocessor with the timer for the main loop ofdata transmission in the receiving-end microprocessor; (n1) starting toreceive data bits, and after the timer for receiving data bits iscleared to zero, restarting the supplying-end microprocessor; (o1)checking the signal flag that indicates completion of receiving todecide if a check is needed; proceeding to step (o11) if check isneeded; otherwise, proceeding to step (p1); (o11) performinginitialization of the transmission power pre-reduction check and controlprogram when the timer for detection of data bit receiving runs for 2.25mS in the supplying-end microprocessor; (o12) checking the triggersignal and deciding that the data length of the end bit signal receivedis 2.5 mS±0.5 mS; (o13) executing the transmission power recovery checkand control program when the timer for detection of data bit receivingruns for 2.75 mS in the supplying-end microprocessor; (o14) transmissionbeing completed, transferring the data into the supplying-endmicroprocessor for internal use and preparing to receive data in thenext data transmission loop, and then proceeding to step (b1); (o15)deciding that data transmission is failed if no triggering happenedwithin the expected time period, executing the transmission powerrecovery check and control program, and proceeding to step (j1); (p1)performing initialization of the transmission power pre-reduction checkand control program when the timer for detection of data bit receivingruns for 1.75 mS in the supplying-end microprocessor; (q1) checking thetrigger signal; if the triggering happened within 2 mS±0.5 mS, decidingthat the data length of logic 0 signal received is 2 mS and proceedingto step (q11); if no triggering happened, proceeding to step (r1); (q11)clearing the timer for detection of data bit receiving to zero at thetriggering point and restarting it, then marking the received datasignal as logic 0; (q12) executing the transmission power recovery checkand control program when the timer for detection of data bit receivingruns for 0.25 mS in the supplying-end microprocessor; (q13) storing thereceived logic bits into Rx data buffer cyclically in sequence from themost significant bit to the least significant bit, and adding one countto the data counter; (q14) checking if the number of data transmissionhas been equal to that of transmitted data bits; if yes, proceeding tostep (q15); otherwise, proceeding to step (q16); (q15) having receivedincomplete data bit, and preparing to receive the trigger next time, andproceeding to step (c1); (q16) the supplying-end microprocessor havingreceived a complete data bit, marking the end bit flag that needs to bechecked, preparing to receive the next trigger and proceeding to step(c1); (r1) executing the transmission power recovery check and controlprogram when the timer for detection of data bit receiving runs for 2.25mS in the supplying-end microprocessor; (s1) executing the transmissionpower recovery check and control program when the timer for detection ofdata bit receiving runs for 2.75 mS in the supplying-end microprocessor;(t1) checking the trigger signal, deciding that the data length of thelogic 1 bit signal received is 3 mS±0.5 mS, and proceeding to step (u1);proceeding to step (o15) if the triggering does not happen; (u1)clearing the timer for detection of data bit receiving to zero andrestarting the supplying-end microprocessor, and then marking thereceived data as logic 1; (v1) executing the transmission power recoverycheck and control program when the timer for detection of data bitreceiving runs for 0.25 mS in the supplying-end microprocessor andproceed to step (q12) continuously.
 7. The method of time-synchronizeddata transmission in induction type power supply system according toclaim 6, wherein the transmission power pre-reduction check and controlprogram in step (c1) comprises the steps of: (c11) initializing thetransmission power pre-reduction check and control program; (c12)checking if the testing voltage on the supplying-end coil of thesupplying-end module has reached the set value to pre-reduce the outputpower; if the set value has not been reached, proceeding to step (c13);otherwise, proceeding to step (c15); (c13) starting the voltagecomparator in the supplying-end microprocessor and preparing to detectthe trigger signal; (c14) terminating the transmission powerpre-reduction check and control program and returning to the mastersystem program; (c15) recording the current operating frequency first,and then increasing the output frequency to the power drive unit toreduce the output frequency from the supplying-end coil when the setvalue range for power pre-reduction is reached; (c16) starting thevoltage comparator in the supplying-end microprocessor to prepare fordetecting the trigger signal, setting the marking for reduced power andproceeding to step (c14).
 8. The method of time-synchronized datatransmission in induction type power supply system according to claim 6,wherein the transmission power recovery check and control program instep (f1) comprises the steps of: (f11) initializing the transmissionpower recovery check and control program; (f12) checking if there is anymarking made for power pre-reduction; if there is no marking, proceedingto step (f13); otherwise, proceeding to step (f15); (f13) no markingmade for power pre-reduction, shutting off the voltage comparator in thesupplying-end microprocessor directly to make it unable to be triggeredwithin the time period and prevent from interfering with datatransmission when no data is received; (f14) terminating thetransmission power recovery check and control program and returning tothe master system program; (f15) restoring to the operating frequencyrecorded previously to make the output frequency to the power drive unitand amplitudes of the output frequency from the supplying-end coilreturn to the signal state prior to power pre-reduction; (f16) shuttingoff the voltage comparator in the supplying-end microprocessor toprevent noise and system error, eliminating markings for powerpre-reduction and proceeding to step (f14).
 9. The method oftime-synchronized data transmission in induction type power supplysystem according to claim 6, wherein in the step of marking the startbit flag as confirmation completed in step (m1), the trigger signaltimer is cleared to zero and restarted for detecting next trigger, andthe timers installed in the supplying-end and receiving-end modules arecalibrated at the same time.